The “Grand Paris” (greater Paris) project was re-launched in 2007 and aims at transforming the greater Paris area into an international metropolis on an equal footing with New York, London or Tokyo. With an additional 1.8 million inhabitants projected to live in the Ile-de-France region by 2030, the flagship project includes the construction of 70,000 housing units, 200 km worth of new subway lines and 72 new stations. It will create one million jobs, especially in high-value-added sectors. The development of the Grand Paris metropolis must contribute to the energy transition effort: with the Ile-de-France region already importing 90% of its energy, it is crucial to assess the future energy needs of the nascent metropolis. Energy savings and renewable sources will have to be encouraged, for instance through the implementation of the Grand Paris Express line.

30% increase in energy consumption in the greater Paris area

However, the new metropolis will result in a 30% increase in energy use, compared with 11% if the Grand Paris project were not undertaken. The increasing reliance on electric vehicles, the new “Grand Paris Express” transport network as well as the proliferation of energy-intensive data centres, account for this gap. It is worth considering, all the more so as Paris already heavily relies on energy supply from the outside. In 2013, about 92% of the Ile-de-France region’s electricity needs were covered by imports. It will not be easy for energy output to keep pace with increasing demand from the new Grand Paris metropolis, which is estimated to reach 2,200 MW by 2030.

Smart grids and renewables to meet extra demand

Installing smart grids will cover some of this additional demand. Moreover, grid infrastructure will have to be operational to meet new needs. That is why French grid operator RTE is in the process of fitting the Nanterre substation with a static var compensator (SVC). This 3,000 m2 smart grid will be activated by the end of the year and will greatly improve power supply quality and security.

Speeding up the development of renewable energy sources and saving energy will be essential as well, especially in the transportation sector, which uses the most energy in France. The Ile-de-France region strives to strengthen its partnership with the Haute-Normandie and Basse-Normandie regions, where off-shore wind farms are expected to generate a sizable electricity output, though not until the end of the decade. The planned shutdown of the Fessenheim nuclear power plant makes this reorientation of the grid all the more pressing.

Other approaches are being considered, such as geothermal power, energy recovery in trains[1] and energy optimization of train stations and the surrounding neighbourhoods.

Lower gas consumption through energy efficiency

According to Grand Paris projections, gas consumption should decrease by 4% by 2030, because of increasing industrial energy efficiency and, above all, thanks to a nearly 25% cut in gas consumption in residential buildings. In order for the Ile-de-France energy system as a whole to be more flexible and secure, gas infrastructure will have to become more adaptable and allow for new uses. Parallel to that, the use of intermittent renewable energy sources is expected to become more widespread. But gas is not the only energy source whose consumption is expected to decrease: home heating oil sales have gone down by 60% between 2000 and 2012, and this trend is likely to continue.

Today the Ile de France region imports almost 90% of its energy. It is therefore crucial to anticipate the needs of the future metropolis in order to improve infrastructure and provide residents with a comfortable and sustainable environment.

[1] Whenever energy is transformed (for instance, heat into motion), “leaks” occur, i.e. no system can be 100% energy efficient. However, some of the energy that gets trapped in materials or leaks out can be recovered.